枕寰枢关节三维有限元模型的建立及其有效性验证  

Establishment and Validation of the Finite Element Model of Occipito-atlantoaxial Complex

作　　者：牛雷 贺瑞[1] 张文志[1] 段丽群[1] 李旭[1] Niu Lei;He Rui;Zhang Wenzhi(Department of Orthopaedics ,Anhui Provincial Hospital, Hefei 230000 ,Chin)

机构地区：[1]安徽省立医院,安徽合肥230000

出　　处：《实用骨科杂志》2018年第5期427-430,共4页Journal of Practical Orthopaedics

摘　　要：目的构建出包含枕骨、寰椎和枢椎以及韧带、关节囊的三维非线性有限元模型,并验证其有效性。方法利用1例青年男性枕颈部CT数据、Mimics软件建立完整枕寰枢三维几何模型,HyperMesh软件对模型完成实体网格划分,添加韧带及关节囊结构单元,生成完整的枕寰枢复合体三维有限元模型。再导入"ABAQUS"软件。进行边界条件约束及载荷设置,使模型产生前屈、后伸、左右侧屈及左右旋转6个方向的运动,计算力矩-角位移变化,并和Panjabi参考值对比。结果我们所建立的枕寰枢关节有限元模型形态贴近真实标本,共有513 601个单元。本模型在1.53N·m载荷下得到的枕寰枢复合体活动度在Panjabi估计参考值的95%内,且各个方向的运动学特征和新鲜尸体标本研究中所观察到的结果相符。结论本研究建立的有限元模型骨骼结构几何形状高度逼真,各种材料属性设计均有文献支持。采用了具有二维结构的膜单元建立韧带和关节囊模型,进一步优化了模型的真实度,同时可以准确分析各韧带在寰枢关节不同运动状态下的应变及应力分布,这是以前的枕寰枢复合体三维有限元模型所不能达到的。特定载荷下的运动学验证说明我们所建立模型的前屈后伸、左右侧屈及左右旋转这些运动学特性,在生理范围应力下均与正常人体极为接近。Objective To construct a three-dimensional nonlinear finite element model of the occipital,atlas,and the axis and verify the validity of the model.Methods Thin layer CT scan were conducted for one male volunteer,scanning data were directly read by Mimics 15.0 software,the three-dimensional geometric model of atlas,axis,and part of the occipital bone were established,then the model was imported into the finite element re-processing software HyperMesh 10.0,by which we add all the ligaments and joint capsulars,meshing all the structures of the model,define the material parameters of all bone structures and soft tissues.Finally,we generated a comprehensive three-dimensional finite element model of occipito-atlantoaxial complex,which was recognizable in the software ＂ABAQUS＂.With ＂ ABAQUS＂ software,we made the model producing flexion,extension,lateral bending,rotatory motion under torsion at 1.50 N·m,computed torque-angular displacement,and compared the values with the reference value of Panjabi＇s.Results This study established a normal finite element model of occipito-atlantoaxial complex,including a total of 513601 mesh elements.When the applied load reaches 1.53 N·m,the range of motion of our model was within the range of 95%reference value in Panjabi＇s study.And all six load torque-rotation angle curves showed obvious nonlinear relationship.The atlantodental interval was 1.22 mm in the neutral position,under the shearing force forward,the ADI were up to 2.8 mm without the failure of the model,which was also consistent with cadaveric experiments.Conclusion The occipitoatlantoaxial complex finite element model developed in this study has highly realistic geometric configuration,two-dimensional membrane element optimized the realistic of the appearance of the model,and we can accurately analyze the strain and stress distribution in different ligaments under different motion state of atlantoaxial joint.Through the validation under certain loads,our model has significant nonlinear kinematic characteristic

关 键 词：枕寰枢复合体 三维有限元 非线性 有效性 

分 类 号：R318.01[医药卫生—生物医学工程]